The present invention relates to a cleaning apparatus for an exhaust path of a process reaction chamber used in a manufacturing process for semiconductors or LCDs, and more particularly, to a cleaning apparatus for the exhaust path in which an inflow pipe and an outflow pipe are formed inside a housing to which a gas inlet and a gas outlet are attached, radio frequency power from a radio frequency generator is applied to the inflow pipe and the outflow pipe, and a capacitor and a coil for impedance matching are provided.
In general, a plasma generator is used in a process of depositing or patterning a structure implemented on a semiconductor or a liquid crystal display LCD. Plasma refers to an ionized gas state consisting of ions, electrons, or radicals, and is generated by a high-temperature state, a strong electric field, or a radio frequency (RF) electromagnetic field.
In particular, the plasma generation by a glow discharge phenomenon is performed by free electrons excited by a direct current (DC) or radio frequency electromagnetic field, and the excited free electrons collide with gas molecules to generate activity groups such as ions, radicals, and electrons. Such activity groups physically or chemically act on the surface of target surfaces to alter the properties thereof.
In this way, a process of intentionally altering the surface properties of a material by an active group is referred to as a surface treatment, and generally, the surface treatment with plasma refers to cleaning or etching the surface of the material by utilizing the products of a plasma state. In the process reaction chamber for executing the surface treatment of the object using the plasma, an exhaust pipe is connected to the process reaction chamber in which a plasma is generated and from which a gas such as argon gas is discharged to the outside. A vacuum pump connected to or in-line with the exhaust pipe causes the exhaust gas to flow to the outside, while gate valves and a pressure regulating valve implement flow and pressure control of the exhaust gas. A scrubber reduces the concentration of harmful substances in the exhaust gas to a level below an acceptable standard prior to discharge of the exhaust gas to the atmosphere.
However, solid precipitate generated by the deposition or etching process taking place within the process reaction chamber may enter the exhaust pipe and accumulate on an interior surface of the exhaust pipe. Over time, this accumulation can cause operational failure of the gate valve or the pressure regulating valve or can lead to interference with the smooth emission of the exhaust gas by blocking the exhaust pipe.
Therefore, an operator needs to manually remove the solid precipitate of the exhaust gas to enable the continuous emission of the exhaust gas. However, since it is necessary to temporarily stop the reaction chamber processing during such manual cleaning, a decrease in productivity results. In addition, since harsh chemicals are used in the manual precipitation removal process, safety risks are also always present.